Long-term durability of b/w slides from fogging second developer

[Hans Borjes]

I am currently fiddling with the Kodak reversal kit. TMAX results have not convinced me. FP4 gives a higher contrast and brightness that is much closer to Scala, which I try to "clone".

For TMAX it was necessary to use a selenium toner to get rid of the yellow-greenish cast and turn it into sepia/brown. It turned out that the intensity of the sepia tone disappears over a few weeks, so that the TMAX becomes greenish again and the FP4 remains only slightly sepia.

As I have seen that some of you guys in this forum have very good chemical background, I would be interested to hear your opinion about the long-term durability that one can expect from b/w slides processed with the fogging agent in the Kodak kit in comparison with a second light exposure and "normal" second developer, e.g. from the Foma kit.

Is it to be expected that these slides remain intact for as long as normal b/w prints (~100 years) or as long as color slides (~40 years)?

 

[Kino]

From my experience with reversal cine film, the archival difference chemical fogging and light re-exposure prior the second development doesn't make a bit of difference if done properly.

PE?

 

[Hans Borjes]

From my experience with reversal cine film, the archival difference chemical fogging and light re-exposure prior the second development doesn't make a bit of difference if done properly.

Interesting. How many years of storing b/w cine film have you seen?

PE?

Hmm. I am not a native speaker. What are you asking?

 

[eumenius]

Hello Hans,

I am making my own BW slides with Ilford films, reversing both FP4+ and Delta 100, always with good results. I mix my own chemistry according to Ilford recommendations, and use dichromate bleach instead of permanganate. What bleach does use Kodak in their kit - is bleaching mix orange (dichromate) or magenta (permanganate)? On my opinion, the emulsion of Ilford films is hardened a bit more than usual, so it retains some residual dichromate even after a clearing bath. Well, the only solution in this case for me is to wash the bleached film in a running water until it clears really well - it may take 15-20 minutes, but then it clears nicely. That's how I do it - and I always tone my slides in selenium later, with no discoloration in a week. Just extend the washing times after bleaching, wash it in the subrued light or darkness, and you should be OK. The residual dichromate in emulsion is no good, of course. I don't use any fogging agent - just a light re-exposure and second development.

Mit Gruess, Zhenya

I am currently fiddling with the Kodak reversal kit. TMAX results have not convinced me. FP4 gives a higher contrast and brightness that is much closer to Scala, which I try to "clone".

For TMAX it was necessary to use a selenium toner to get rid of the yellow-greenish cast and turn it into sepia/brown. It turned out that the intensity of the sepia tone disappears over a few weeks, so that the TMAX becomes greenish again and the FP4 remains only slightly sepia.

As I have seen that some of you guys in this forum have very good chemical background, I would be interested to hear your opinion about the long-term durability that one can expect from b/w slides processed with the fogging agent in the Kodak kit in comparison with a second light exposure and "normal" second developer, e.g. from the Foma kit.

Is it to be expected that these slides remain intact for as long as normal b/w prints (~100 years) or as long as color slides (~40 years)?

 

[Hans Borjes]

Zhenya,

The Kodak kit contains in the bleach
* potassium permanganate
* sulfuric acid

and in the redeveloper
* hydroquinone
* polymeric glycol
* potassium sulfite
* dimethylamine borane.

I have not seen Ilford Delta 100 slides yet, how would you describe them in relation to FP4 slides?

Privjet, Hans

 

[Gerald Koch]

There should be no difference in the archival characteristics of slides regardless of which second development method is used.

 

[Jordan]

There's a third way to achieve the second development -- with an alkaline solution of sodium sulfide or thiourea. (These are equivalent to the second bath of a bleach-and-redevelop sepia toner kit.) This should also be very archival (in the same way as a sepia-toned print).

 

[Kino]

Interesting. How many years of storing b/w cine film have you seen?

30 or so years myself, but the archive I work for has been storing film copies since 16mm was introduced in the 1930's and in speaking to the old-timers around here, there seems to be a consensus that it did not matter within the deterioration parameters of the base; i.e. , the base will fail either way prior to the chemical interaction affecting the emulsion becomes a substantial factor.

If it were a factor, the failure rate of chem fogged film would show in some manner over film re-exposed via light exposure, but it has not.


Hmm. I am not a native speaker. What are you asking?[/QUOTE]

Sorry, I was asking PhotoEngineer to jump in here with his opinion; I was a bit to0 cryptic, I am afraid!